Epson S1C6S3N2, Техническое руководство

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I-62
EPSON
S1C6S3N2 TECHNICAL HARDWARE
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Clock Timer)
The clock timer can cause interrupts at the falling edge of
32 Hz, 8 Hz and 2 Hz signals. Software can set whether to
mask any of these frequencies.
Figure 4.8.2 is the timing chart of the clock timer.
Interrupt function
Clock timer timing chart
Frequency Register Address
070H
D0 16 Hz
D1
D2
D3
8 Hz
4 Hz
2 Hz
32 Hz interrupt request
8 Hz interrupt request
2 Hz interrupt request
Fig. 4.8.2
Timing chart of
clock timer
As shown in Figure 4.8.2, interrupt is generated at the
falling edge of the frequencies (32 Hz, 8 Hz, 2 Hz). At this
time, the corresponding interrupt factor flag (TI32, TI8, TI2)
is set to "1". Selection of whether to mask the separate
interrupts can be made with the interrupt mask registers
(ETI32, ETI8, ETI2). However, regardless of the interrupt
mask register setting, the interrupt factor flag is set to "1" at
the falling edge of the corresponding signal.